Geotechnical Engineering & Underground Infrastructure

Seismic Retrofit of Pile-Deck Wharf Structures

Abstract: Many port facilities in the North America are vulnerable to severe damage in major seismic events. The most critical structures are pile-supported wharf decks that are often founded within loose/uncompacted fills. Lateral spreading (and potential liquefaction) of the fill slopes during an earthquake can cause bending failure of the piles and collapse of the wharf. The main goal of this research is to investigate the effectiveness of retrofit methods for improving seismic performance while causing minimal disruption of port operations. Research on this topic was originally supported by NSF through a NEESR-Grand Challenge project (led by colleagues at Georgia Tech.). The MIT research used the framework of OpenSees to simulate the underlying (free-field) ground response that is then coupled to the structure through macro-element representations of pile-soil interactions. Studies to date have shown the effectiveness of PV drains as a method of mitigating structural damage for a broad suite of ground motions. On-going studies aim to improve the modeling of cyclic response of the soils to enable more realistic predictions of seismically induced slope failures.